Motor



De. 15, 1942'. E. e. EPPENS 3 9 MOTOR I v Filed July 29, 1941 2Sheets-Sheet 1 INVENTOR H I 5 ATTORNEY.

Dec. 15, 1942. E. G. EPPENS 2,304,903

MOTOR Filed July 29, 1941 2 Sheets-Sheet 2 INVENTOR 51 48 E'znestIIZ:/'ppeu5.

H l5 ATTORNEY:

Patented Dec. 15, 1942 MOTOR Ernest G. Eppens, Alpha, N. 3., asslgnor toIngersoll-Rand Company, ration of New Jersey New York, N. Y., a col-pApplication July 29, 1941, Serial No. 404,470

Claims. (Cl. 121-121) This invention relates to motors. and moreparticularly to a motor employing a plurality of reciprocatory pistonsfor imparting movement to a rotary member.

One object of the invention is to minimize the cost of constructingmotors of this type.

Another object is to provide a rugged and compact motor having a minimumnumber of parts that may be cheaply maintained and replaced.

Other objects will be in part obvious and in part pointed outhereinafter.

In the drawings accompanying this specification and in which similarreference numerals refer to similar parts.

Figure 1 is a longitudinal elevation, partly brokenaway, of the motorconstructed in accordance with the practice of the invention,

Figure 2 is a perspective view, partly broken away, of a detail, and

Figures 3, 4, 5, 6, 7, 8, and 9 are transverse views taken throughFigure 1 on the lines 3-3, 4-4, 5-5, 6-6, 1-1, 8-8, and 39,respectively.

Referring more particularly to the drawings, the motor designated ingeneral by and shown, by way of example, as being of the pressure fluidactuated type, comprises a casing 2| having a crank chamber 22 at oneend which is closed by a plate 23. A boss 24 on one end of the plateextends into a recess 25 in the casing to maintain the casing and theplate 23 in coaxial relationship with each other. The plate 23 may besecured to the casing 2| in any suitable manner, as for example by bolts26.

In the form of the invention illustrated, the casing 2| is provided witha plurality of radial bores, four in the example shown, forming pistonchambers 21 that open with their inner ends into the crank chamber 22and are sealed at their outer ends by cover plates 28. Within ach pistonchamber is a reciprocatory piston 29 for actuating a rotary shaft 30journaled in bushings 3| and 32 arranged in the plate 23 and in thecasing 2|, respectively.

The pistons 29 are of the free-floating type, that is to say, they arecapable of movement within the piston chambers 21 relatively to theshaft 30. Within the pistons are stems 33 that preferably project beyondthe skirts of the pistons and have seating surfaces 34 on their freeends.

The seating surfaces 34 are shown as being flat and engage theperipheral surface 35 of an eccentric 36 on the shaft 30 and lying inthe crank chamber 22. As a preferred arrangement, the eccentric 36 isencircled by a band. 31 that may be attached to the eccentric in anysuitable manner to provide a renewable bearing surface for the seatingsurfaces 34 of the pistons.

The stems 33 are coaxial with the piston chambers 21 and theirlongitudinal axes extend through the axis of rotation of the shaft 30.They are hollow, having cylindrical. bores 36 the end surfaces of whichconstitute pressure surfaces 39 that are subjected to pressure,preferably fluid pressure, for holding the seating surfaces 34constantly in engagement with the surface 35 of the eccentric. Thepressure fluid serving this purpose is conveyed into the recesses 36 bypassages 40 in tubular projections 4| on the inner surfaces of the coverplates 26 and extending into the recesses 38.

The passages 40 lead through the cover plates 28 and the casing 2| andopen into an annular supply groove 42 in the end surface of the casing2|. The plate 23 serves as a cover for the supply groove 42 and has apassage 43 that communicates with a supply conduit 44 connected to theplate 23.

The outer end surfaces of the pistons 23 constitute actuating surfaces.45 which are subjected intermittently to power medium, as for examplecompressed air, and are sealed from the pressure surfaces 39 by thetubular projections 4| which cooperate with the walls of the recesses 33to prevent communication between said recesses and the piston chambers21. Such power medium is conveyed to the piston chambers 21 by passages46 in the casing 2| and the bushing 32 and opening into the bore 41containing the rearward end of the shaft 36, which, in the form of theinvention shown, constitutes a valve 43 for controlling the flow ofpower medium to and the exhaust of fluid from the piston chambers 21.

The valve 48 is provided in its periphery with a pair oflongitudinallyextending grooves 43 and 50 each of which may serve to valve pressurefluid to the pistonchambers or to control the exhaust of pressure fluidfrom the piston chambers, depending upon the direction of rotation ofthe shaft 30. The pressure fluid supply for the grooves 49 and is,however, supplied to said grooves by different channels. To this end thegroove 49opens into an internal annular groove 5| located in the bushing32 rearwardly of the passages 46 so that when the groove ii is servingas a supply groove pressure fluid flows therefrom through the groove 49into the inlet passages 46.

The groove 50 serves a similar function and affords communicationbetween the inlet pas:- sages 46 and an annular internal groove 62in Thepressure fluid used for actuating the pis tons 29 is conveyed to thegrooves BI and 52 by passages I53 and 54, respectively, leading from. athrottle valve chamber 55 and are controlled by a throttle valve 56 inthe chamber 55. The throttle valve 58 is of the rotatable type, having alever 51 whereby it may be shifted to the diflerent controllingpositions, A bore 58 extending part way through the throttle valve opensinto the inner end of the chamber 55 and is in direct communication withthe annular supply groove 42 through a passage 58 leading from thethrottle valve chamber to said annular groove 42.

Communication is afforded between the bore 58 and the passages 53 and 54by ports 69 and 6!, respectively, in the wall of the throttle valve andlying in different radial planes. The throttle valve is, moreover,provided in its periphery with a partly annular groov 62 that lies inthe same transverse plane as the port 60 and opens into a longitudinallyextending groove 63 in the periphery of the throttle valve. The groove63 opens at its rearward end into an annular external groove 54 in thethrottle valve and the latter groove is in constant communication with afree exhaust port 65 in the casing 2 l. The forward end of the groove 63opens into a partly annular groove 68 in the transverse plane of theport 61 to afford communication with the passage 55, and the freeexhaust port 65.

The throttle valve may be held in the chamber 55 in any suitable manner,as for example by an externally threaded sleeve 61 threaded into thecasing 2| and having an internal shoulder 68 to seat against a collar 69on the periphery of the throttle valve.

In order that the crank chamber 22 will be constantly vented the shaftis provided with a radial passage i9 that communicates constantly withthe crank chamber 22 and with a passage H extending rearwardly throughthe shaft 30. The passage H opens into a space 12 in the casing 2!rearwardly of the bushing 32 and the space 12 is in communication withthe atmosphere through a port 13 in the casing.

The operation of the device, briefly described,-

is as follows: With the movable parts of the motor positioned, forexample, as shown in the drawings, pressure fluid will flow from theannular supply groove 42 through the throttle valve, the port Gil andthe passage 63 into the annular groove thence through the longitudinallyextending groove 49 and one or both of the passages 46 of the twouppermost piston chambers 21, it being understood thatthe groove 49 isof suflicient width to communicate simultaneously with two of thepassages 46.

The pressure fluid thus admitted into these piston chambers will actuatethe associated pistons 29 to impart thrusts against the eccentric member36 for rotating the shaft 30. During such admission of pressure fluid tothe uppermost piston chambers 21 the groove 50, which is also ofsufficient width to simultaneously communicate with two passages 46,will establish communication between one or both of the lowermostpassages 46 and the annular groove 52. The fluid in the lower pistonchambers 21 will then escape through the associated passages 46, the

83, 84 and the. exhaust port 65 to the atmosphere. The lowermostpistomwill, however, be held firmly against the eccentric member 36 bythe pressure fluid acting against the pressure surfaces 39.

During the subsequent rotation of the shaft the groove 49 willsuccessively communicate the passages 46 with the annular grooves 5| forcharging the piston chambers, and the groove 50 will successivelycommunicate the passages 48 with the annular groove 52 for exhaustingthe fluid from the piston chambers to the atmosphere. This is the modeof operation of the parts for causing the shaft 30 to rotate in aclockwise direction as Figure 1 is viewed from the left hand end.

If it be intended to operate the shaft 30 in a counterclockwisedirection and with the parts in the positions shown in the drawings, thethrottle valve 56 is rotated to bring the port 6| into registry with thepassage 54 and to move the port 60 out of registry with the passage 53and at the same time to bring the partly annular groove 62 intocommunication with the passage 53. In the new position of the throttlevalve pressure fluid will flow through the passage 54, the annulargroove 52 and through the longitudinally extending groove into the twolower piston chambers 21.

Such pressure fluid acting against the associated pistons 29 will causethe shaft 30 to rotate and the fluid in the upper piston chambers 21will be expelled through the associated passages 36, the grooves t9, 5!and the passage 53 into the partly annular groove 62, whence it passes,through the grooves 63 and 6t and the exhaust passage 65, to theatmosphere.

While I have, in this application, specifically described a form of theinvention employing pressure fluid, such as compressed air, as the powermedium, it, will readily be understood by those skilled in the art thatthe invention may be readily modified for use as the power element of aninternal combustion motor without departing from its spirit or the scopeof the appended claims.

Iclaim:

1. A motor, comprising a casing having a plurality of piston chambers, arotary member having a portion located eccentrically thereon, pistons ofthe free-floating type reciprocable in the piston chamber seatingagainst the said portion,

grooves 50 and 52, the passage 54, the grooves 86,

a pressure surface on each piston constantly subjected to power mediumfor holding each piston against the said portion, an actuating surfaceon each piston intermittently subjected to power medium for impartingdriving movement to the pistons for actuating the rotary member, andseparate power medium supply passages for the pressure surface and theactuating surface.

2. A motor, comprising a casing having a plurality of piston chambers, arotary member having its axis of rotation extending through thelongitudinal axes of all the piston chambers,

means on the rotary member presenting a surface loeatedeccentricallywith respect to the axis of rotation of the member, pistonsof the free-floating type reciprocable in the piston chambers seatingagainst the surface, a pressure surface on each piston constantlysubjected to power medium for holding each piston against the firstmentioned surface, an actuating surface on each piston intermitmntlysubjected to power medium for imparting driving movement to the pistonsfor actuating the rotary member, and separate power medium supplypassages for the pressure surface and the actuating surface.

3. A motor, comprising a casing having a plurality of piston chambers, arotary member having its axis of rotation extending through thelongitudinal axes of all the piston chambers, means on the rotary memberpresenting a surface located eccentrlcally with respect to the axis ofrotation of the member, pistons of the freefloating type reciprocable inthe piston chambers, a hollow extension on each piston to seat againstthe said surface, a pressure surface within each hollow extension, meansfor introducing power medium to the pressure surfaces for holding theextensions constantly against the first mentioned surface, and anactuating surface on each piston of larger area than the pressuresurfaces and being intermittently subjected to power medium forimparting driving movement to the pistons to actuate the rotary member.

4. A motor, comprising a casing having a plurality of piston chambers, arotary member having a surface located eccentrically with respect to theaxis of rotation of said member, pistons of the free-floating typereciprocable in the piston chambers having portions to engage the saidsurface, pressure surfaces'on the pistons constantly subjected to powermedium for holding the pistons against the eccentrically locatedsurface,

actuating surfaces on the pistons, means cooperating with the piston forpreventing communication between the pressure surface and the actuatingsurface, and valve means operated by the rotary member for effecting thedistribution of power medium successively to the actuating surface tocause the pistons to impart thrusts to the first mentioned surface forrotating the rotary member.

5. A motor, comprising a casing having a plurality of piston chambers, arotary member having a portion located with respect to the axis ofrotation of said member, pistons of the freefloating type reciprocablein the piston chambers having seating surfaces to engage the peripheralsurface of the said portion, a pressure surface on each pistonconstantly subjected to power medium for holding the pistons againstsaid portion, an actuating surface on each piston, means cooperatingwith the piston for preventing communication between the pressuresurface andthe actuating surface, a valve operated by the rotary memberfor effecting the distribution of power medium successively to theactuating surface to cause the pistons to impart thrust to the saidportion for rotating the rotary member, and means for controlling thedirection of rotation of the rotary member.

ERNEST G. EPPENS.

